Hi All
I did a mistake. I got two copies of my project. One is updated but the other must be an old version (call it "old-v").
old-v
hadn't updated for more than 2 mounths and some files changed but not
commited (not the same like 2 months ago). That means the updated and
the old-v are becomed diffirent projects. Last friday when I wanted to
update the updated one, Unluckly I updated old-v.
How can I make the old-v like before the updated on friday?

If I can't express myself, let me show it with a simple example:
2m ago: the project on SVN server was "aaaaaa"
now the main project become on SVN server like "bbbbbb"
but my second project was like "aaaacc" until I hit the button "update" wrongly
and now the second project is like "bbbbcc".

But there is rarely a reason to use such an old release. All 1.x
releases are backwards-compatible and offer too many fixes &
enhancements to pass up. Additionally, when used properly (with Apache
or svnserve for the server), all 1.x clients are compatible with all
1.x servers, so there's no reason to attempt to "match" client &
server versions.